Tabular reference device.



No. 762,546'. PATBNTED JUNE 14, 1904. A. H. MERRILL. TABULAR REFERENCE DEVICE.

APPLIGATIOH FILED PEB. 17. 1902.

PATENTED JUNE 14, 1904..

A. H. MERRILL. TABULAR REFERENCE DEVICE.

APPLIGATION FILED rma. 17. 1902.

'IIS-SHEET Z.

Nuwumu No 4 SH LETS-SHEET 3.

PATENTED JUNE 14, 1904.

A. H. MBRRLL.

APPLICATION FILED FEB. 17. 1902.

TABULAB. REFERENCE DEVICE.

2 E t 2 s 9520x052 o @m2o n llovombwo mit.

No MODEL.

avvo- PATENTED JUNE 14, 1904.

A. H. MERRILL.

TABULAR REFERENCE DEVICE.

APPLIGATION FILED FEB. 17,V 1902.

Bgm Elo 030405 O6 O7 OB O9 ftlll llllrllfll lill-.Ill vllftllllllf.

rfllltll Illlll .IIIIIIIIII Patented June 14, 1904.

PATENT OFFICE.

ALBERT H. MERRlLL, OF FLORENCE, CALIFORNIA.

TABULAR REFERENCE DEVICE).

SPECIFICATION forming part of Letters Patent No. 762,546, dated June 14, 1904. Applieationiiled February 1'7, 1902. Serial No. 94,544. (No model.)

To (1,71 whom it may concern: Bc it known that 1', ALBERT H. MERRILL, a

citizen of the United States, residing at Florence, in the county of Los Angeles and State of California, have invented anew and useful Tabular Reference Device, of which the following is a specification.

This invention` may be applied to various display devices, and among others relates to that class of calculators in which a table showing results calculated from certain data is so arranged on relatively moving parts that by properly manipulating the same any desired result within the capacity of the device may be exposed to view at a sight opening or openings.

An object `of this invention'is to provide in a small compass, as in a series of cards arranged in pack form, a table or tables of great extent which the user can instantly and conveniently adjust to exhibit the result Which he desires to determine. By reason of the cards being held in pack form the device may be of a size that can readily be carried in the pocket and yet embrace a table of calculations equal to that contained by a much larger device otherwise constructed, or a table so large as to heretofore require figures too small to be easily read when contained in a pocket device may be contained in an equal compass by my device and yetbe printed in larger and easily-read type. I attain this desirable end by providing means for singly extending intermediate cards of the pack in combination with devices for holding against frictional displacement the card or cards contacting withithe one operated.

By this invention it becomes possible toprovide within the compass of aconvenient deskruler or a case which can be carried in the pocket tables of multiplication and division involving several digits in the result. The invention may be embodied in diierent ways and for different purposes.

An object of this invention is to provide a device of this class which will be convenient, simple, compact, inexpensive, and accurate,

' being capable of supporting in convenient position for instant and convenient examination a number of slides bearmg tables of cal,-

culations which may be quickly adjusted to enable persons to ascertain at a glance the total cost of any given quantity of merchandise at a determined price when the total money value and the price per unit of Weight or measure are known.

My invention is therefore adapted to be substituted for the more expensive computing devices now in use in the form of attachments to weighing-scales, being capable of embracinga larger table of numbers than is used with computing-scales and requiring less time for operation than is required to set a pair of computing-scales.

Although primarily intended for use in performing mathematical operations, the mechanism of my tabular reference device may also be used for an indexer, a mechanical directory, or for a list of Words alphabetically arranged, sueh as might be found in a list of Words dicult to spell or in a small dictionary. It Inay also be used to display samples of paint, cloth, wall-paper, &c.

The invention embraces a tabular reference device comprising a plurality of superposed sliding members having tabulated information thereon, a cover for said members, means for sliding any desired member a predeterminate distance to bring the desired portion of said member into view, said means comprising means for operating and means for stopping such member. The means for operating and the means for stopping any member may be variously constructed Without departing from the broad terms of this invention. Preferably the means for operating any member Will comprise an arrangement of seats in the members, respectively, and a removable instrument to engage said seats, respectively, thereby to slide the members, and an arrangement of stops on the cover to stop saidinstrument when it strikes the same. The several seats will be appropriately marked to indicate the character of the tabulated information which will be brought to view at the appropriate place when the instrument is thus stopped, and preferably each of the sliding members will be furnished with a plurality of sight-openings, and the cover Will also be furnished with sight-openings, the parts be- IOO ing constructed and arranged to normally provide a sight-opening or sight-openings entirely through the appliance, so that when any of the slidingb members is moved from the normal position information carried thereon will be visible through the sight-opening or sight-openingsfrom either side of the appliance.

Each of the sliding members mayhave the same information arranged on its opposite sides,l so that when' certain information is exhibited to a person on one side of the appliv ance the same information will be visible from the other side, or, if desired, the appliance may be constructed with a portion of certain tabulated information on one side and an extension of like tabulated information on the other side, thus to embody an extensivetable within a small appliance.

Preferably the sliding members will have perforations through them to receive an instrument by which to be moved and will be so constructed and 'arranged that the perforations of all the sliding members will be open at both sides of the appliance when the parts are in normal position. l

The accompanying drawings illustrate the invention in some of the forms in which I propose to embody the same.

FigureI is a side view of a device embodying the invention in a form convenient for carrying in ones pocket. Parts of the cover of the box or casing are broken away to show parts underneath. Fig-II is a longitudinal section on line II II of Fig. I. Fig. III is la fragmental enlargement of a portion of Fig. II. Fig. IIIL'is a fragmental sectional detail illustrating the arrangement of the elasticcords and the plates,which are yieldingly held in normal position thereby. Fig. IV is an enlarged cross-section on line IV AIV of Fig. I. Fig. V is an enlarged cross-section taken on line V V of Fig. I. Fig. VI is a vside view illustrating the operation of the device. This View practically'illustrates the reverse side of the device as shown in Fig. I, with the exception that a modification of the retracting mechanism and of the frame, box, orcasing is shown. Fig. VII is a View of the edge of the device as shown in Fig. VI. Fig. .VIII is a cross-section on line VIII VIII, Figs'. VI and VII. Fig. IX is a view of a blank for a eli p adapted to hold the frame together and also to provide means for readily attaching and detaching the elastic cords which retract certain parts inside the frame. Fig. X is a detail of a form of device for applying to the plates the pressure of the elastic cords. Portions of a cord are shown. Fig. XI is a side View of aform of the device adapted to be used for both multiplication and division and also containing certain modifications, especially in the retracting mechanism. By the appliance shown in this view the quantity of a commodity may be d( termined when the total value `and the price per pound are modified form of retracting mechanism on line XIII XIII of Fig. XII. -K Fig. XIV is an lend view of the part shownin Fig. XIII looking right from left of Fig. XI. Fig. XV is a cross-section on line XV XV of Figs. XI

vided with my invention. Fig. XVIu shows in detail a feature of construction of Fig. XVI. Fig. XVII is an enlarged fragmental view of the same, the cover being omitted, parts being broken away to show interior construction. Fig. XVIII is a fragmental plan of one of the covers. Fig. XIX is afragmental longitudinal section illustrating the retracting mechanism, being taken from line XIX XIX of Fig. XVII. Fig. XX is a fragmental longitudinal mid-section of Fig. XIXon irregular line XX XX. Figs. XXI and XXII are cross-sections taken, respectively, on lines XXI XXI and XXII XXII of Fig. XVII.

For convenience of description I will consider first the invention as illustratedin Figs. I to X, inclusive. The cover-or frame may be composed of two side members C C', held apart by edge pieces A and A and end pieces B B', the whole. being fastened together by any suitable means, glue, solder, or hsome other suitable substance with and without clips, respectively, being used in the two forms under consideration. In'Fig. VI four clips a (1)2 a,"l a* are shown attached to the corners of the frame to strengthen it. 'The said covers C and C may be of pasteboard, celluloid, metal, or other suitable material and are preferably of the same size and shape, each containing a' row of equidistant transverse slots or sightopenings c c2 c3 and also alarger and more nearly square combined sight and operating opening c".

Between the covers C C' are slidingly mounted a plurality of superposed exhibit members, preferably in the form of plates f. f f2 f* f. These plates are each provided with a plurality of sight-openings c c"l c3, preferably of the same size. and shape as the corresponding openings in the covers. When the parts are in normal position, the openings in the sliding plates all 'coincide with each other and with the corresponding openings in the covers, so that normally the openings extend entirelythrough the device at the sight-openings of the covers. Each of the sliding plates is desirably furnished at one end with aperforated actuating-arm, as shown at g g' g2 g3 g4. Said varms are preferably integral with the body portions of their respective sliding plates and are provided with means for moving them, as seats or shoulders, preferably formed as rows L LZ l1. It* of perforations. The outer arms g and g* may be broader than thel other Fig. XIII is v and XII. Fig. XVI is a plan of a ruler proroo arms, if desircd,to add to the strength of the device. This will be understood/.by reference to Fig. I, where the characters'4f and 5t designate `the end corners of the arm g, and the characters 27'. and 28 designate the like corners of the arm g, while 1 4;t andldesignatc 4the like -corners of the arm g.

- sliding `plates actuated by the first-mentioned retracting device. Y

Various forms of resilient retracting devices may be employed. In the forms shown in Figs. I and VI elastic .cords are used for retracting the sliding plates. -The alternate sliding plates are respectively provided with a notch k, and the other sliding plates are provided with a notch k'. j and j designate elastic cords which extend across the forward ends of the sliding plates and are caught in the notches l: 7c', respectively, of such plates, so that when any plate is drawn to the right in Figs. I to VI the cord which is in the notch of that plate will be extended, so that when the plate is again released the cord will retract it. The plates are constructed and arranged to respectively engage only one of the cords, each cord leaving free the plates engaged by the other cord. The purpose of arranging the cords to operate the alternate plates, respectively, is to assemble the sliding plates as close together as possible without causing the operation of one to actuate the others by friction thereupon.

Where a clip for the elastic cord is employed as hereinafter described, the cord will be applied in two sections, the ends of which areconnected with the clip and the frame of the device, respectively.

In the particular construction illustrated by Figs. VI to VIII, inclusive, the covers C C', respectively, have two longitudinal slots il i', each slot being opposite -the corresponding one in the other cover. Two endless elastic cords jj are arranged to pull against the sliding plates at the notches'k 7s' in the ends of the said plates. These notches do not show in Fig. VI, but occupy the same position as in Fig. I, where they are clearly shown. The clips a and a2 are preferably formed as metal plates, as shown in Figs. VI, VII, and IX, being furnished with hooked portions a e', upon which the extremities of the cords j j' are looped, as shown in Figs. VI and VII. This arrangement makes it possible to easily rempve a cord as soon as it has been broken or weakened by use and to put on a new one. The end pieces B B. are preferably formed with raised portions or beads 7) on each side., In the end piece B each of these raised portions contains two notches b', as shown, so that when the device is laid upon a plain surface its weight does not bear upon the cords j j. By this arrangement the cords are guarded against wear and their free movement during `the operation of the device while lying on a plain surface is provided for.

In the form of my invention shown in Figs. I to V, inclusive, the cords jj are placed inside the covers, being single instead of double at the point where they pass over the notches lf: lo. In this arrangement stronger cords should be used, and they should be looped over the end piece B before the frame' is put together. A notch f, Fig. I, may be cut on three sides off the end piece B at the points designated, so as to keep the cords jj in place and sink them to the level of the surface of the end piece. These elastic cords normallykeep all of the plates in the retracted position, as shown in Fig. I.

If no reference is made to the notches/c k', the outline of each offthe live 'sliding plates,

(shown in Figs. I to VL) including the arms by which they are to be operated, respectively, may be described* as follows, each number indicating the position of an ,external corner. Referring to Fig. I, the corners of the plate f and its arm g lie at the points designated by lf 2t 3i 4f 5f (if 7 f 8t 9i 10g. The external corners of and its arm g lie at 1i 11 12i 3 13 141' 15c In Fig. VI, to avoid confusion, the cornersare not all designated, the outermost forward corners 4f andZSf of plates f and f4, respectively, and the corner-s 23f and 24F of the arm g3 of plate f 3, which is there shown out of normal position, being the only corners marked. From this description of the form of the plates it will be seen, referring to Figs. I and III", that the .cord y' normally holds the rst or upper plate f and the third and fifth plates f2 and f* in the retracted position, and the cord j in like manner retains-the second and fourth plates f and f 3 in the retracted position. The cut-away portions of the plates next to the notches 7c 7c are thus so arranged that only one cord is extended at a time by the operation of a plate, the other cord retaining its normal position and holding against frictional displacement the plate or plates next to the one being operated.

The slots in the covers of the case and in the plates are each preferably of a less width than the portion of the cover between the adjacent slots, and each plate is movable at variant distances, so that the desired indicators, as numbers, colors, orother desired matter on anyplate, may be brought into view by moving the plate the proper distance.

The numbers-Z of thetable are placed on the plates in columns and longitudinal rows, the spaces d' of the columns corresponding with the distances between the centers of the perforations through the arms g g', &c., seen from each side of the appliance through one or the other of the large openings c4.

The opening c4 is substantially as wide as the distance between the adjacent spaces, in order to permit of each column of numbers on each of the plates being brought into register with the openings in the case. By constructing the parts in this manner the number of slots or openings in the case may be limited in numbr without decreasing the capacity of the instrument, and at the same time greater accuracy is secured by locating the columns of numbers on the covers so far apart that they are not confusing.

.-In operating the device to consult the table a pointed instrument may be used in the ordinary way. The numbers in the table on the body of the plates are so arranged with relation to the perforations in the rows it It', &c., that when the point of a pencil p or other suitlable instrument is inserted into a perforation and its plate is thereby moved until the instrument strikes the stop formed by the edge c5 of the aperture, as shown in Fig. VI, three 'numbers of each longitudinal row of the portion of the'table on the slide or plate will come into View, one being seen through each of the slots c c2 o3, as is clearly shown in Fig. VI. On the outer sides of the covers, alined with the longitudinal rows of numbers on the body of the plates, are numbers in columns rr' r2, extending along one side of each of the slots c" c2 c3', respectively;

When the device is to be used for multiplition, the numbers in the table represent the products obtained when the. numbers on the covers are used for one set of factors and the numbers on the arms are used for the other set of factors. These three sets of numbers` viz., those on the body of the plates, those on the arms, and those on the covers-are so arranged with relation to each other that the products of mu ltiplications may be determined in the following manner, as is clearly illustrated by Figs'. VI and VIII. l

To multiply any number contained in the set of numbers comprised in the columns r r r2 by 32, for example, insert the point of the pencil or other instrument p into the perforation marked' 82 and pull the plate f3 to the right until the instrument strikes against the edge of the-opening c4, which constitutes the stops c5 for all of the plates, when the plate f3 will be vvin the position shown in Fig. VI. When the plate is in this position, the product of one-fourth multiplied by thirty-two`viz., eight-will appear opposite i3 which is the top number in the column r; 640, the product of thirty-two multiplied by twenty, will be exposed in line with the number 20, and so on with all the numbersembraeed by the device. After a desired prod uct has been ascertained the instrument p may be removed and one or the other of the elastic cords jj' (the cord j in the present instance) will return the plate to its normal position.

The operating-aperture c4 on each side of the case exposes all of the operating-openings .it in the normal position of the slide. Each operating-apcrtu re constitutes a cut-away portion of the case opposite the aperture in the other side to enable the operating means to penetrate the slide without obstruction by the case.

From the foregoing description the mode of operation will be plain, since it is uniform in all cases. Attention need only be called to 'the fact that the numbers on the arms may run'from or other chosen number to 25 or any other suitablenumber on one side and from the latter to 50 or some other suitable number on the other side, omitting any numbers-such as 1, "5, or 10, for instance-which may be deemed desirable to omit. The numbers in the columns r r r2 may or may not bethe same on'both sides of the device. Since the operating instrument p may be inserted into the perforations from either side, the capacity of the device is double what it would be if it could be operated from one side only. v

The perforations are desirably located along the mid-length of the arms g g', &c., and said arms overlap each other nearly to the perforations, which construction is adapted to make them firm and strong'as possible. If desired, the perforations may be eyeleted, or thin metal strips may be attached 'to the arms having perforations coinciding with those in the arms.

r3 designates index-numbers at the tops of the several openings c', c2, c3, and c* to indicate at a glance the limits ofthe factors pertaining to said openings, respectively.

In order to avoid obscuring by shadows the' figures which are close to the edges of the openings c c2 o3 and also in order to make allowance for any inaccuracy of adjustment of a plate when the same is brought into a reading position, said openings c' 02 c3 are somewhat wider than the columns of the figures to be read therethrough.

The opening c3 is preferably made a little shorter than the openings c and c2, so as not to weaken the sliding plates too much where they are cut away oppesite the ends of the said Aopening c3.

The elastici cords jj tend to draw togethe the forward ends of the plates. In some cases this may cause friction enough to interfere with the proper retracting of the plates. To

avoid this, a rigid clip may be used, as illustrated in Fig. X. This clipmay consist of a wire bent, as shown, at the points j* and furnished with hooks j3'for the attachment of the elastic cords.

IOO

IIO

IIS

` the corresponding openings in a platel above or below the same. To avoid this, small cords or wires s may be strung across the said openings.` These cords s may be passed through holes s' s near the ends of every alternate plate, the ends of each cord being connected together on the other side of the plate, so as to form a loop. If the cords are drawn tight .enough to take up the slack, they will effectually remedy the diiculty referred to. This arrangement will also tend to separate the numbered faces of the plates from each other, thus preventing the characters from being worn off by friction.

When the slides are composed of cardboardor similar material, it may be desirable to employ some means to prevent fraying or roughening along the edges. This may be done by applying glue or some other suitable sizing.

In the device as shown in Fig. XI each of the sliding plates is intended to have the same table of numbers on its opposite sides, and the covers are also intended to be numbered alike, so that when a result is exhibited to a person on one. side ofthe appliance the same informatlon will be visible from the other side.l

Any convenient means (not shown) may be used to support the appliance in an edgewise position in order to more readily accomplish this purpose. i l

The appliance as shown in Fig. XI is adapted to be used for both multiplication and division, the s ace on the portion of the sliding plates to t e left of the opening c6 being occupied by a multiplication-table, while that to the right of this opening contains a table adapted to show'the quantity of a commodity when the total value and the price per pound are known. dzindicates the pounds-columns. (Z3 indicates the ounces-columns. These columns are so spaced that when a computation is made the pounds-column will aline with the heading lb's.at the top of the opening c7, and the ounces-column will likewise fall under the heading oz. The numbers in said columns are only approximate in some instances, nothing less than one-fourth ounces being noted in the form shown. r6 designates acolumn of iigures which ind icate the money value of the amount purchased. The function now under 'consideration will be best understood by giving an illustration. To find what weight at one-half cent per pound can be purchased for anyjmoney value indicated in the column fr, insert the operating instrument p' into the perforation to the right of and move the same to the right until stopped by the stop c, This will bring the left-hand Weight-indicating columns d2 d3 into view at the sightopening c7. The number "10 will appear under the heading lbs. and opposite the number 5, thus indicating that live cents will purchase ten ponnls at one-half cent per pound, and so on down the column. lt' the operating. instrument had been inserted into the perforation to the right of 1t,3 would have appeared opposite 5 under the heading lbs. and 5i would be seen under the heading oz., thus indicating that iive cents will purchase three pounds live and onefourth ounces at one and one-half cents per pound.

The mode of operating the various embodiments of the invention is-uniform. Conse- -quently the manner of using the device shown in Fig. X1 will be readily understood from the foregoing description.

When small characters are used in connection with a large number of plates, it Vmay be difficult, owing to the depth of the hole through the upper plates through which the result must sometimes appear, to associate the appropriate number on the cover with the appropriate result-indicating number on a rearward plate. This dii'neulty may be overcome by separating the numbers on the plates into sections by means of horizontal lines (Z5 and correspondingly dividing into sections the numbers in the indicating-columns 'r3 /r of" fr by short horizontal lines fr?. The lines (l5 and T7 are alined with each other, as shown, and preferably separate the numbers in the columns into groups of five to facilitate locating the desired known quantities in reading the result.

Each number on the arms may be placed on the side of its perforation opposite its stop, so that such number (which always indicates one of the known quantities of a problem) may be seenv next to the operating instrument when the slide is fully moved to show the desired result.

In Figs. X to XV, inclusive, means are shown for applying the retracting force simultaneously to each edge of the plate operated, thus to insure a more even action of the plate. D y and E indicate two hollow rods running lengthwise the frame near each side thereof. The said rods constitute means for supporting the retracting mechanism, which is the same on each side of the device and is therefore, for convenience of description and illustration, described and fully shown only in connection with the rod E. Said rod E forms a guide for two external followers F F and an internal follower (Jr. The said external followers F F may be respectively formed by fitting a collar F", desirably rectangular in external outline, to one end of a sleeve and fastening it thereto by a screw F4 or y The screw F* enters a screw-threaded hole through one side of the collar F, passes on through a hole in the sleeve F2, andprojects into the rod E through a slot E2 through the wall thereof. The vfollower F' is constructed the same as the follower F, exceptingthat the screw F", which l IOO Vsliiles in the slot E, does not project far v rod E. Every alternate sliding platef, '7,

vthe external springs ,&c., is provided with two projections yaand u', upon which the collars of the external followers F bear in returning the plate toits normal position. 'lhc other plates fnfl, &c., are furnished with projections 11.211,, whereby they are returned to normal position by the pair of followers F' which are actuated by 1, the followers F being actuated by the internal springs H. By this arrangement every plate is returned to the normal position by pressure applied to both sides through the ears or projections.

In Figs. XI and XII, K K" indicate-guidingstrips to keep the forward ends of the sliding plates in place. These guides are provided with lugs K2, which project through corresponding holes in the covers to keep the said guiding-strips in place.

In Fig. XI another means is shown for avoiding the danger of the plates catching upon each other, hereinbefore referred to. Referring to theopening c, the left edge thereof slants to the rightat the ends, as shown at ci and c, so that when the plate is operated it first closes the opening near the corners cl2 and cla and in thus passing in between the plates above and below the bow thereof, if any, is at least partially removed before the central portion of the opening is closed up, so that there is less danger of a plate catching upon those nextito it above or below. The

' openings ci c, &c. are equal ly spaced apart, the said openings being desu-ably' space between greater than the length of the extreme forward movement of the slides, so as to leave. next to the left side of room for a margin m each section of the table between the openings c c, &c., so that in the extreme forward position of any plate during its operation no edge will appear through any of the openings c c5, &c. Hence no plate can at any time catch at the beginning of the retracting movement. The covers may be composed of two metal plates or side pieces A2 A3, connect-r ed together along the four edges by the strips B5 B, which are clenched to the said covers by means of ears B7,'being bent down into depressions A and B", formed in the side plates. The depressions A4 in each cover serve Inot only for seats for the ears B7, but also for means to keep the slid ing plates from working in between the covers A2 A3 and the followers F F on either side. The covers A2 A3 are be'nt over and may, be brought together at thel ends. The guide-rods I) and E have a segment cut away at cach end. (Indicated by E.) When the parts are assembled,

` followers F10 Fl1 `mounted thereon.

the ends of the said rods are fitted into semicircular openings AG through the end portions of the strips B and B, respectively, all longitudinal and rotary play being thus avoided.

Figs. XVI to XXII, inclusive, illustrate the invention as applied in a ruler. The body portion Al0 of the ruler is chambered out, as shown by solid and dotted lines at N in Fig. XVI, the covers C1" and .(Jl being fastened to each side by any suitable means to inclose the chamber, thus to form a case or frame for the parts. 'lhe sliding` plates f2 fi, &c., shown in these views are of the same construction and arrangement as in Figs. I and VI except that they are more elongated and contain nine perforations in each arm instead of five. The retracting mechanism is applied to the sliding plates in amanner similar to that shown in Figs. I and VI, but consists of slidingly mounted upon guide-rods E10 E11 and retracted to normal position by springs Il In. Said followers F'" F may each be composed of two pieces, a U-shaped piece F12 embracing the guide-rod and connected by solder or other suitable means to a piece F, said piece F1I`x being provided with a shoulder or bent-out portion F, adapted 4to engage the shoulders f "m f l of the sliding plates. The sides of the chamber N may be grooved at n., being that portion opposite the opening cl3. Said grooves a may be shaped to correspond with the convex portion of the U-shaped piece F12, thereby providing means for preventing any rotary movement ofl the followers. Holes O may be formed as shown to provide sockets for the rods El" E1l and the sprin gs I10 I, respectively,

The object of' these sockets is to provide for the use of as long springs as possible.

In Figs. XVI, XVII, and XVIII, r" and d,

respectively, indicate lines on the cover and on the plates. These lines assist in locating and readingy the result in the same manner as lines f7 and (Z5 described in connection with Fig. XI.

Plugs Q may be employed to hold in place the forward ends of the guide-rods El. En. When the parts are assembled, the end'-of a rod is slipped into the socket q and the plug is fitted into the forward end of a hole O, being secured therein by glue or any other suitable means. l

In multiplying nineteen and one-half by thirty-two use the perforation marked 32 and mentally add together the products of nineteen multiplied by thirty-two and onehalf multiplied by-thirty-two, both of which are shown at the same time. This method may likewise be employed in many other cases where one factor is a mixed number.

When the multiplicand contains more than two figures, proceed as follows: To multiply two thousand one hundred and forty-two by thirty-two, insert the operating instrument into the perforation' marked "32 and 'note TOO IIO

tlu product of twenty-one (which comprises the first two figures of the multiplicand) times thirty-two and also of forty-two (the last two figures of the multiplicand) times thirty-two, both of which products appear at the same time. (See Fig. lVI.) Add two ciphers to the right of the product of twenty-one multiplied by thirtytwo,thus obtaining sixty-seven thousand two hundred. To sixty-seven thousand two hundred add one thousand three hundredand forty-four-the product of forty-two multiplied by thirty-two. The Sum of these two partial products is sixty-eight thousand rive hundred and forty-four, the total product of two thousand one hundred and forty-two multiplied by thirty-two.

If instead of two thousand one hundred and forty-two multiplied by thirty-two wehad one i hundred andv eighty-two thousand one hundred and forty-two multiplied by thirty-two the products'ot eighteen multiplied by thirtysame price per unit of weight or measure, it

two'and forty-two multiplied by thirty-two would all still appear at the same time, and an operator fairly vproficient in mental arithmetic could do the necessary carrying and add-i ing without writing down any numbers.

A device for doing this kind of work would have to contain the products of all whole numbers up to one hundred multiplied by one hund red; but a calculator of such capacity, it constructed according to the principles of this invention, could still be made small enough to carry in the pocket.

W hen the device is used in an edgewise po` sition, it may sometimes be desirable to entirely omit the retracting mechanism, since each plate rests upon the frame and there is practically no friction of one plate upon another.

If most of the sales being made-are at the maybe desirable to leave a plate in a reading position, so as not to have to operate it everyI time a sale is made. Thus, if the retraetingcords were removed and the plate gain Fig.

' VI were not manually adjusted. the device would continue to indicate the total money value of a commodity selling at thirty-two cents per unitof weight or measure. They plate could be returned by the operating instrument when desired. l

What I claim as new, and desire to secure by Letters Patent of the United States, is-

1. In a device of the class described, a series lof slidable plates each provided withan arml or projection containing a row of apertures,

said arms overlapping each other at their edges; substantially as described.

2. In a tabular reference device, a frame, a plurality of longitudinally-slidable plates,an elastic cord and an inelastic clip secured to the ends of the cord and extending across the forward ends 'of said plates in position to be engaged thereby and to return said plates to their normal position. i

3. In a tabular reference device, the combination of a frame; sliding plates;`retract1ng cords for said plates; .and combined means for strengthening the frame and attaching and devtaching the cords. l

' 4. In a device of theclass described, a slot-- ted ease', one of the slots being wider than the others, and one of its walls forming a stop, slotted indicating-plates movably mounted in the case, each plate being provided with an arm which extends across said wider slot, said arm being provided with a'series of perfora-v tions, and movable so as to move each perforation into a position adjacent to said wall.

5. In a device oi' the class described, a slotted case, one of the slots being wider than the.

others and one of its 'walls forming a stop, the distance between the adjacent narrower slots being substantially equal to the width of the wider slot, slotted plates in the ease, the slots in the plates corresponding with those in the ease, and each plate being provided with a plurality of indicators foreach slot and with a shouldered arm which extends across the Wider slot, said shoulders being movable into a position adjacent to said wall and its correspending indicator into register with Aits respective slot in the case.

6. In a device of the class described, aslotted case, one of the slots being wider than the others and' one of its walls Jforming a stop, the distance between the adjacent slots being substantially equal to the width of the wider slot, and each slot having a column of numbers adjacent thereto, and slotted plates in the ease, the slots of which correspond with slots in the case, each plate being provided with a plurality of columns of numbers for each slot, and with a shouldered arm which projects across the Wider slot, there being a shoulder for each column of numbers at any slot, said shoulders being each movable into a position adjacent to said stop whereby its respective column of numbers is brought into register with the slots in the case and in the other plates.

7 In a device of the class described, a perforated case, stationary supports for the same, the' support at one end being notched, clips at said endv provided with projections registering with said notches, perforated plates in the case, inelastic clips in4 position for engaging with said plates, and elastic cords secured to said inelastic clips and extending through said notches and detachably engaging with the projections on theelips at-that end of the case. 8. In a device of the class described, in combination, a case, a series of plates inclosed in said case and provided with arms containing longitudinal rows of operating-apertures, said rows bf vapertures being normally exposed on both sides through openings in the case, the plates being superposed in said series and slidable in the same direction. v

9. In a device of the class described, a case having sight-openings and a slide within said TOO bered operating-openings on the slide in the normalposition of the latter, the ends of said operating-apertures being adapted to act as stops for operating means inserted through said operating-openings. c.

10. ln adevice ofthe class described, in comlbination, a series of superposed movable, members, means for singly extending intermediate members of the series, and two retracting devices for the series, one device engaging with alternate members and the other device with the intermediate members.

11. In adevice of the class described, in combination, a series of superposed movable slides, means for singly extending intermediate members of the series, and twp elastic cords adapted to retract the entire series, one cord engaging with alternate slides and the other cord engaging with the other slides.

12. In a device of the class described, in combination,a series of superposed longitudinallyslidable plates placed in contact with each other, a suitable casing having one or more sight-apertures, and an elastic retractor engaging forward edges of a plurality of the. plates, and thereby holding against frietional displacement thc plate or plates contacting with the one being operated.

13. In adevice of the class described, in combination, a series of su perposed longitudinallyslidable plates having contacting faces, a suitable easing containing one or more sight-apertures, and'two retracting devices each engaging forward edges of a plurality of the plates, and thereby holding against frictional displacement the plate or plates in contact with the one being operated.

14. In a device of the class described, in combination, a frame, aseries of superposed slides, and two automatic retracting devices, each yieldingly holding alternate slides of said series and leaving free the slides held by the other.

15. In a dvviee of the class described, in combination, aframe, aseries of superposed slides, and two elastic cords each yieldingly holding alternate slides of said series and leaving free the slides held by the other.

16. In a device ofthe class described, in combination, a frame, aseries of superposed slides,

two automatic retracting devices one of which normally engages shoulders of alternate slides of the series and the other normally engages shoulders of the intervening slides, said slides having eut-away portions preventing more than one retracting device from being operated at a time.

17 In a device of the class described, in combination, a perforated case, plates slidably mounted therein, elastic cords exterior to the case for engaging with the plates and automatically returning them to the normal position, and supports on the sides of the ease adapted to prevent said case from resting upon the cords when it is laid on a plain surface.

18. In a device of the class described, in combination, a perforated case, plates slidably mounted therein, elastic cords exterior tothe ease for engaging with the plates and automatically returning them to the normal position, and means adapted to prevent said case from resting upon the cords when it is laid on aplain surface.. f

19. In a tabular referencedevice, in combination, a cover having transverse sightapertures, a correspondingly-apertured slide having a row o"f seats, and a stop in line with said seats, the distance between the stop and the scat normally farthest therefrom substantially equaling the distance between two adjacent slots of the slide.

20. ln a tabular reference device, a series of cards held in pack form, a perforated case inelosing said cards, definite characters upon the cards, definite characters upon the ease, means whereby a card may be moved and a character thereon brought into definite rela- 'tion with a character on the case, and two devices, each yicldingly holding alternate cards and leaving free the cards held by the other.

21. In a tabular reference device, in combination, a frame, a plurality of transverse columns of numbers inscribed thereon; a plurality of superposed plates movably mounted within said frame, said plates having a plurality of transverse slots corresponding respecti vely to the columns of numbers on the frame,

Aeach plate` being provided with a succession of seats arranged in a longitudinal row; and

a stop in line with the seats in said row, the

distance between the seat normally farthest from the stop and the stop being substantially equal'to the distance between two adjacent slots of the plate.

22. In a tabular reference device, a perforated case, a series of cards held therein in pack form, characters on the'cards, and characters on the case, one of said cards having a.

plurality of means wherebythecard maybe moved a distance relatively to the position of said means, and two devices, each yieldingly holding al tornate cards and leaving free the cards held by the other.

23. In a tabular reference device, a perforated case, a series of cards held therein in pack form, characters on the cards, and characters on the case, one of said cards having a plurality of seats whereby the cards may be moved variant predeterminate distances, said distances corresponding to the position of the seats, relatively to one of the walls of one of IOO IIC

the perforations in the case, and two devices, i

resenting the unknown quantities of mathe'- matical problems inscribed upon the cards,

numbers representing the known quantities,

means for moving a card to expose to vlew` the number representing the'unknown quantityV of a problem in definite relation with a number representing one of its known quantities, and two devices, each yicldingly holding alternate cards and leaving free the cards held by the other.

' 25. In a tabular reference device, a perforated case, a series of contacting cards -movably mounted therein, each card having a body portion occupying substantially the entire inner width of the case, definite characters upon the cards, definite characters upon tbe case, means whereby a card may be moved and a character thereon exposed to view in definite relation with a character on the case,

- and two devices, each yieldingly holding alterJ nate cards and leaving free the cards held by lthe other.

umns of designating-numbers inscribed thereon a plurality of superposed plates movably mounted within said frame each of said plates being provided with a longitudinal row. of

seats, .there being indicating-numbers for said seats, said plates each also having a plurality of transverse slots corresponding respectively to the aforementioned columns of designatiing-numbers on ythe frame; a table of numbers on the plates, eachspace between two adjacent slots of a plate bearing thereon a division of the table arranged with the numbers in longitudinal rows and transverse columns, each of the longitudinal rows being in line with its designating-numbers on the frame, and the columns of each aforementioned division of the table corresponding respectively to the aforementioned seats of the plate.

' Y 28. In a tabular reference device, in combination, a cover provided with a plurality of transverse slots; a column of desi gnating-numbers along a side of each of said slots; a plurality of superposed plates movably mounted beneath the cover, each of said plates being provided with a longitudinal row of seats, there being indicating-numbers for said seats, said plates having transverse slots normally coinciding with the slots inthe cover; a table of numbers inscribed on the plates, each portion of. a plate between two adjacent slots bearing thereon a division of the table having the numbers thereof arranged in longitudinal rows and transverse columns, the columns of each said division of the table corresponding respectively with the aforementioned seats of the'plate, so that, throughout its several divisions of the table columns corresponding to each other are provided with a common seat.

29. In a tabular reference device, in combination, a frame; and a series of superposed perforated plates` each plate of the series having a portion eut away from the lateral edge adjacent to one side of the frame, the intervening plates each being'cut away from the other lateral edge, for the purpose specified.

30. A tabular reference device comprising a frame; a plurality of transverse columns of designating-numbers inscribed thereon; a longitudinally movable plate mounted in the frame; a table of numbers arranged in longitudinal rows and in groups of transverse eolumns, each ofthe longitudinal rows alining with its proper designating number on the frame, said plate being also provided with a succession of seats equal in number to the columns of any given group so that columns correspondingto each other throughout the several groups may have a common seat; and a -stop for said seats.

31. A tabular reference device comprising a frame; a plurality of transverse columns of designating-numbers inscribed thereon; a longitudinally'- movable plate mountedA Within the frame; a table of numbers on the plate arranged in longitudinal rows and in equal groups of` transverse columns, ea'eh'of the longitudinal rows alining with its proper designating-number on the frame, Said plate ybeing also provided with a succession of perforations adapted to receive a removable instrument from either side thereof, said perforations being equal in number to the columns of any given group so that columns corresponding to each other throughout the several groups may have a common seat; and a stop for said seats.

32. In a device of the class described, in combination, a frame; a series of superposed slides; means for moving said slides from the normal position; and two elastic cords respectively attaehed to the-rear portion of opposite sides of the frame and extending over forward IDO IOS

slides having eut-away portions preventing more than one cord being extended at a time by the operation of a plate.

In a device of the class described, in

combination, acover, a column of designating-- numbers thereon, a longitudinally-slidable plate within said cover, a group of numbers arranged in longitudinal rows and spaced columns on said plate, each row in line with a number of the column on the cover, there being a numbered operating-seat corresponding to each column on the plate, and a stop for the seats wherebyT the column corresponding to any seat maybe displayed adjacent to said column on the cover. y t

34. In a device of the class described, in combination, a frame, a longitudinally-movable plate within said frame, a-cover for said plate,atransverse column ofdesignating-numbers along an edge of the cover, a group of numbers arranged in longitudinal rows and spaced columns on the plate, each row corresponding'to a number of the column on the cover, there being a numbered operating-seat corresponding to each column in the group of numbers on the plate, and a stop for the seats whereby the column corresponding to any seat may be displayed adjacent to said edge of the cover. l

` 35. In adevice ofthe class dcscribed,a series of superpesed longitudinally-slidablc plates, a suitable casing'having a sight-opening, and an elastic retractor engaging forward edges of a plurality of the plates..

36. A device of the class described, a case having sight-openings, and a slide within said case provided with numbers exposable through said sight-openings, said slide being provided with numberedoperating-openings, and said' ALBERT H. MERRILL.

Witnesses:

VJAMES R. TowNsEND, JULIA TowNsEND. 

